/*****************************************************************************
 * Given an array of integers, find if the array contains any duplicates.
 * Your function should return true if any value appears at least twice in 
 * the array, and it should return false if every element is distinct.
 *****************************************************************************
 * 2015-07-09
 * NJUST,NanJing JiangSu
 *****************************************************************************/


#include <algorithm>